Treatment of Resistant and High-Risk Humeral Non-union Cases with rhBMP7
Introduction: Non-union of the humeral shaft is a rare condition. In these patients, more stable fixation with or without autograft results in nearly 95% union rate. The purpose of this study was to evaluate bone union following use of recombinant human bone morphogenetic protein-7 (rhBMP7) for treating humeral non-union.
Material and methods: This was a prospective study of resistant non-union cases treated by repeated fixation and addition of rhBMP7. The case series consisted of 16 patients with an average age of 53.8 years (24-71). Patients presented with non-union of the humeral shaft and had experienced at least one failed attempt at surgical repair. Osigraft® (rhBMP7) was added to the non-union site after decortication, medullary canal reaming and fixation with one or two plates. The average time elapsed between the initial fracture and the second revision was 31 months (5-103). The patients had undergone an average of 2.3 procedures (1-6).
Results: All patients were reviewed after at least 24 months of follow-up. No neurological complications were reported. One failure occurred in a non-compliant patient with septic non-union who had undergone four previous procedures. The other patients experienced bone union after an average of 12.4 months (6-14), with no further procedures required. The patients were able to return to their normal daily activities.
Conclusion: Failure of the initial fracture treatment (unstable fixation, postoperative bone defect) is the primary cause of non-union. Although autograft is the gold standard treatment for non-union cases, the course of action to take if this primary strategy fails has not been defined. During secondary use (due to failed autograft procedure) and when there is no requirement for a structural graft (humerus can be shortened), providing stable fixation and adding a growth factor leads to bone union even in a septic environment.